1. Field of the Invention
This invention relates to a tube end support for locating a tube end in a tube coupling.
2. Background Prior Art
My European Patent Publication No. 0756126 discloses a tube coupling comprising a coupling body having a throughway open at one end to receive a tube, the diameter of the throughway increasing towards said open end at a first step to form a first enlarged diameter portion to receive a tube and a second step to form a second enlarged diameter portion to receive a tube locking device to hold a tube in the coupling body. A thin wall sleeve has one end engageable in the throughway and the other engageable in the tube to be located in the coupling body so that, in use, the sleeve extends from the tube past the first step into the throughway. The sleeve has a sealing engagement with the internal diameter of the tube to prevent leakage between the sleeve and tube and the end of the sleeve projecting from the tube has an annular seal with seals with the throughway in the coupling body to prevent leakage between the sleeve and coupling body.
The invention provides a tube end support for locating a tube end in a tube coupling, comprising a sleeve to be received in a tube, an encircling end stop adjacent one end of the sleeve to limit entry of the sleeve into the tube, encircling gripper means on the sleeve to grip on the internal diameter of a tube to hold the tube on the sleeve and a separate annular seal supported by the end and projecting radially outwardly thereof to seal with the internal diameter of a tube coupling in which the assembly of the end support and tube are located.
In one arrangement according to the invention the sleeve is formed with an encircling head at said one end thereof which provides the end stop for limiting insertion of the sleeve into the tube and supports the separate annular seal for sealing with the internal diameter of the tube.
More specifically the head may have an encircling annular groove around its periphery and an O-ring seal is mounted in the groove to connect radially therefrom for sealing with the internal diameter of the tube.
The aforesaid gripping means for gripping the internal diameter of the tube may comprise an integral annular barb formed on the outer diameter of the sleeve facing towards the head at the end of the sleeve, over which the tube must be forced when inserting the sleeve into the tube to grip and hold the sleeve in the tube.
In an alternative arrangement said one end of the sleeve may have an encircling head projecting outwardly of the sleeve, a gripping means comprising an annular barb formed integrally with the outer diameter of the sleeve at a spaced location from the head to grip the internal diameter of the tube inserted over the sleeve, and a collar of elastomeric material extends around the sleeve between the barb and head with an outwardly projecting annular flange adjacent the head extending beyond the outer periphery of the head to provide a seal with an inner diameter of a connector body in which the assembly is located.
In the latter arrangement the elastomeric collar has a raised annular ridge encircling the outer periphery of the collar to seal with the internal diameter of the tube.